ENHANCEMENT OF THE BRUCELLA AMOS PCR ASSAY FOR DIFFERENTIATION OF BRUCELLA-ABORTUS VACCINE STRAINS S19 AND RB51

Because the brucellosis eradication program uses slaughter and quarant ine as control measures, it would benefit from faster methods of bacte rial identification. Distinguishing vaccine strains from strains that cause infections among vaccinated herds in the field is essential. To accomplish this, our PCR-based, species-specific assay (B. J. Bricker and S. M. Halling, J. Clin. Microbiol. 32:2660-2666, 1994) was updated to identify Brucella abortus vaccine strains S19 and RB51. Three new oligonucleotide primers were added to the five-primer multiplex Brucel la AMOS PCR assay. Identification is based on the number and sizes of six products amplified by PCR.